KAERENU ONI TO NO MOMO BIYORI

Otaku salaryman, Momose, who loves fantasy and parallel worlds, comes upon a book that he used to read a lot in the past: “The Complete Collection of Summoning Magic”. Feeling nostalgic, his middle-schooler heart re-ignites, so he decides to try and chant once again the summoning spell to call The Servant of Fate... But suddenly, in doing so, a demon named Keiha comes out of his closet?!

(Source: Media Factory, translated)